悬索桥主缆与鞍座摩擦特性理论分析方法

Theoretical Analysis of Cable-saddle Friction Characteristics for Suspension Bridges

为了研究主缆与鞍座间摩擦力的组成机理,给多塔悬索桥的设计与施工提供参考,对主缆与鞍座摩擦特性的理论分析方法进行了研究,基于接触面间的相互作用力关系建立了主缆索股与鞍座摩擦特性的理论方程和子鞍座并联模型。通过模型试验对所提出的分析方法进行了验证,在此基础上对主缆与鞍座间摩擦特性的关键问题进行了研究。结果表明:所提出的分析方法适用于主缆与鞍座摩擦特性问题研究;主缆与鞍座间的总摩擦力主要由索股与承缆槽底面接触面的摩擦力及索股与承缆槽侧壁接触面的摩擦力两部分组成,其中前者占较大比例;主缆与鞍座间摩擦因数及抗滑移安全系数的取值问题较为复杂,结构设计时应综合考虑多种因素以确定其合理取值。

In order to study the composition mechanism of friction between the main cable and saddle and provide reference for design and friction characteristics between the main construction of multi-pylon suspension bridges, the cable and saddle were analyzed. The theoretical equations and parallel sub-saddle model were established based on the mutual acting forces between the main cable and saddle. The validity of the proposed analysis method was demonstrated by the model test. The key problems of friction characteristics between the main cable and saddle were studied. The results show that the proposed analysis method can be applied for the analysis of friction characteristics between the main cable and saddle; the total friction force contains two main parts, one is the friction between strands and saddle bottom contact and the other is that between strands and saddle side contact, and the former is notably larger than the latter~ in order to determine the sensible friction coefficient and anti-slip safety factor, many factors need to be taken into consideration in design.